A circuit as the one defined in the introduction is disclosed by International Application PCT/FR2009/052719 in the name of the Applicant.
However, the circuit presented by this International Application can only be operated with a limited number of distinct capacities, i.e. in this case, six positive capacities and six negative capacities (by ‘positive’ or ‘negative’ capacity, are meant here, with reference to a predetermined direction of circulation of the fluid, capacities for which the fluid circulates in the predetermined direction or in the direction opposite to the latter, respectively).
Now, as indicated by said International Application, there exists a need for hydraulic circuits having a large number of different capacities, and thereby having great operative flexibility allowing variation of the speeds and of the driving torque in order to adapt the operation of the machine according to circumstances.